Causes of an acute heart failure (i.e. normal sized heart):
- acute myocardial infarction
- ruptured interventricular septum – causing VSD
- acute valvular regurgitation
- mitral valve prolapse (papillary muscles dysfunction)
- usually associated with AMI
- aortic (infective endocarditis)
- mitral valve prolapse (papillary muscles dysfunction)
- acute pulmonary embolus
- cardiac tamponade

Kurmani S, Squire I. Acute Heart Failure: Definition, Classification and Epidemiology. Curr Heart Fail Rep. 2017 Oct;14(5):385-392. doi: 10.1007/s11897-017-0351-y. PMID: 28785969; PMCID: PMC5597697.